issue: 3586273 Use XLIO_DEFERRED_CLOSE by default

For incoming sockets - no change.
For outgoing sockets - since outgoing sockets occupy a local port, we
should release it on the socket destructor to prevent race from another
socket to use the same port.
This race might cause XLIO to hold 2 sockets with the same RFS object at
the same time, and this is fatal (particularly for TCP).

Signed-off-by: Iftah Levi <iftahl@nvidia.com>

src/core/util/sys_vars.h

@@ -872,7 +872,7 @@ extern mce_sys_var &safe_mce_sys();
 #endif /* DEFINED_UTLS */
 
 #define MCE_DEFAULT_LRO                            (option_3::AUTO)
-#define MCE_DEFAULT_DEFERRED_CLOSE                 (false)
+#define MCE_DEFAULT_DEFERRED_CLOSE                 (true)
 #define MCE_DEFAULT_TCP_ABORT_ON_CLOSE             (false)
 #define MCE_DEFAULT_RX_POLL_ON_TX_TCP              (false)
 #define MCE_DEFAULT_TRIGGER_DUMMY_SEND_GETSOCKNAME (false)